<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        *{
            margin:0;
            padding:0;
        }
        .box {
            padding-top:100px;
            border-bottom:1px solid black;
        }
        /* webpack 会自动把小于 8k 的图片自动转换成 base64 格式 */

        @media only screen and (-webkit-min-device-pixel-ratio:2) {
            .box {
                border-image:url() 0 0 2 0 stretch;
            }
        }
    </style>
</head>
<body>
    <div class="box"></div>
    <img style="width: 100px;" src="" alt="">
</body>
</html>